1. Related Applications
The present application claims priority to Japanese Patent Application Number 2006-234963, filed Aug. 31, 2006, the entirety of which is hereby incorporated by reference.
2. Field of the Invention
The present invention relates to apparatuses and methods for displaying images of vehicle surroundings. In particular, the present invention relates to a surrounding-image display apparatus and display method for causing cameras to capture surrounding images of a vehicle and displaying the captured images together with a vehicle image.
3. Description of the Related Art
A system in which images of the rear side of or an area around a vehicle are captured by a camera or cameras attached to the vehicle and are displayed on a vehicle-mounted monitor to assist the driver in driving the vehicle into a garage or in parking the vehicle is under research and is also in practical use. As such a system, a top-view system is known (refer to Japanese Patent Document No. 3300334). In the top-view system, as shown in FIGS. 10A and 10B, cameras 6a to 6e for photographing the surroundings of a vehicle 1 are attached thereto. Using the images captured by the cameras 6a to 6e, an image synthesis processor 7 creates a synthesized image of a landscape viewed in a predetermined direction from a predetermined position (a virtual viewpoint) 8 above the vehicle 1, as shown in FIG. 10C, and displays the synthesized image on a monitor 9, thereby assisting the driver, for example, in parking the vehicle and driving the vehicle into the garage.
In the known top-view system, the display scale is constant for the entire screen (i.e., equal-scale display) so as to make it easier for the driver to get a sense of distance. That is, a surrounding image is displayed at the same scale as that of the vehicle image (see FIG. 11A). However, with such a display method, when the scale of a vehicle image 1a is increased, the display area of the vehicle surroundings is reduced to make it difficult for the driver to recognize the state around the vehicle. Conversely, when the surrounding area displayed on one screen is increased as shown in FIG. 11B, it becomes difficult to see details of the image. Currently, the vehicle image and the surrounding image are displayed at a scale such that an image within about 2 meters around the vehicle can be displayed, as shown in FIG. 11A. However, although such a display method makes it easier for the driver to get a sense of distance to an object displayed on the screen, there is a problem in that the area displayed on the screen is small.
Thus, as shown in FIG. 12, for example, a technology in which top-view display TVEW and back-view display BVEW are simultaneously performed is available. In this technology, however, the screen is divided into two sections to display images; therefore, it is difficult to see a surrounding image of the vicinity of the vehicle, as in the case in which an image is displayed at an increased scale.
Also, when the display area is merely increased, i.e., when equal-scale display is performed, an image far away from the vehicle is displayed with a reduced resolution. Thus, there is a problem in that blurring in an image far away from the vehicle becomes more noticeable than an image of the vicinity of the vehicle.